Gina, I would just add, that on citrus trees, and on every type of tree for that matter, the energy manufactured by the branches growing from the bottom portion of the trunk, distribute all their energy to the trunk, and not to the upper portion of the tree. Therefore if the low growth is left attached and growing, the tree develops a much stronger, thus larger, trunk base. I leave all branches attached throughout the seedling's culture, and only remove the bottom branches two weeks before I'm ready to T-bud. After reading your post I'll now remove them three weeks before budding.
Millet
William Hart - Hero